


God of Mischief and Growing Up

by Liu



Category: DCU, Marvel Cinematic Universe
Genre: De-Aged Bruce, Loki is helping, M/M, Pre-Slash, mostly - Freeform, only not really
Language: English
Status: Completed
Published: 2015-04-09
Updated: 2015-04-09
Packaged: 2018-03-22 01:30:43
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,086
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3709813
Author URL: https://archiveofourown.org/users/Liu/pseuds/Liu
Summary: <blockquote class="userstuff">
              <p>Written years ago as a response to a challenge... and now I realized I haven't posted this and there needs to be more Loki/Bruce, even though it's kinda shitty XD</p><p>I'm not tagging for underage because nothing really happens when Bruce is de-aged, plus he retains the mind of an adult except for some childish impulses.</p><p>(Most likely includes a bit of OOC-ness for Bruce, since this fic is based more on a Bruce/Loki RP with a friend than on some actual canonical work XD)</p>
            </blockquote>





	God of Mischief and Growing Up

**Author's Note:**

  * For [Gemenice](https://archiveofourown.org/users/Gemenice/gifts).



At first, Alfred and Dick thought it was just the fact that he finally got some sleep that made Bruce look younger, and they paid it no attention. Bruce didn’t complain, and it was nice seeing him without the worry lines around his mouth once in a while.

It was when he couldn’t wear his Bat-costume any longer because it was slightly too big that it became obvious that something was amiss.

Bruce grumbled about it and then went to Lucius to get a smaller costume, muttering something about goddamned aliens and their ridiculous magic.

The next morning, the new costume was too large as well and Bruce was eye-to-eye with Dick. That was alarming enough to admit that he had a problem. And a big one at that, no pun intended.

Bruce’s first reaction was to approach the problem through science. Because let’s face it, things that sparkled and shone and produced unpredictable results could NOT be trusted. Flash, Atom and Bruce locked themselves in a lab and ran all the possible (and a few impossible) tests on Bruce’s revitalizing body… but found nothing except the fact that his cells had developed a way to rejuvenate themselves. That didn’t really explain why he was currently at about sixteen years of age; Atom suggested an injection that would slow cell regeneration as such until they figured out the core of the problem.

The next morning, Dick was an inch taller and Bruce was about thirteen. With a deep scowl, Bruce rolled out of his bed, got rid of the too-large pyjamas in favor of Dick’s old jeans and a shirt (which made him feel a bit queasy because it meant he was smaller than Dick, and the boy was enjoying it with loud giggles, even if he cast a worried glance at Bruce here and there) – and called Zatara.

The magician cast a round of spells on him, some of which felt really, REALLY unpleasant, and the effect was that the next morning, Bruce woke up to ten years of age and a mild panic attack (which, of course, he kept completely secret). At the rate this was going, he had about three or four days to live… and then… he’d probably decompose into two or three cells and then disappear… or something. He had no idea how this worked, but he didn’t care much to find out. He took a deep breath and slid out of the bed – it was disconcerting that he couldn’t even reach the floor while sitting on the mattress anymore – and scowled up when he sensed motion at the door.

“Get out,” he growled, but his childish voice did not really feel like obeying him and sounding menacing.

Loki merely leaned against the wall, long arms crossed over his chest and a smirk on his face.

“Is that truly the attitude you would wish to employ with the only person who can help you?”

“I don’t need your help,” Bruce scowled, feeling particularly petulant about help from supervillains who blew up cities and got in league with shitheaded, evil Lithuanian kings. And especially not from supervillains who didn’t even belong to HIM. Help from Flash’s supervillains, he could handle… maybe. But THOR’S? Loki didn’t even belong into this world.

And his hair was ridiculous.

“Oh?” the bastard smirked. “I’ve heard otherwise. How are you enjoying your second childhood? From what I heard, it comes to old mortals just before death.”

Bruce threw a pillow in Loki’s direction and told himself it was simply because there wasn’t much else to throw in the room. The pillow stopped mid-air in front of Loki’s face and dropped harmlessly to the ground. Damn.

“What do you want?” Bruce huffed, and Loki had the audacity to chuckle.

“Me? You are the one in need of help.”

Bruce’s eyes narrowed at that.

“How do you even know?”

That was when another head stuck into the doorway and Bruce felt like throttling someone at that moment. Most likely the yellow-green-red someone who was peeking at him sheepishly.

“He’s the most powerful magician we know, Bruce,” Dick mumbled and Loki snorted.

“Sorcerer, if you please.”

“That,” Dick agreed and gave Bruce a pleading look. Bruce did his best to scowl, not pout, in response.

“How did you even find him?”

“I hacked into the Avengers’ system. Called Thor. They were kinda in the middle of something at the moment with Loki.”

“In the middle of me trying to murder him,” Loki explained with a sunny smile and Bruce groaned. HOW exactly was this going to help…?

“Get out, I’ll handle this,” Bruce growled in the end.

It did not work. Loki rolled his eyes and in a flash, he was at Bruce’s side, pushing him down onto the bed. Bruce’s eyes widened and he struggled, kicking the god’s side, because he felt another panic attack bubbling up in his chest, one caused by being weak in the face of a force like Loki. Dick was in the house, and so was Alfred, the two people Bruce loved most, and then there was the enraged, evil god Bruce couldn’t really beat now.

He could try – he kicked again, and Loki’s face darkened: Bruce was pressed into the mattress by his throat and a tingly, not entirely pleasant feeling spread over his skin. _Magic_ , Bruce’s panicking brain offered, and the thought wasn’t exactly calming. Bruce tried to pull away, grabbing Loki’s hand still pressing down on his throat – but it was very much like trying to shift a whole building.

 _Now I’m going to die, like this, in my bed, with a pissed-off god… that’s so lame_ , Bruce thought, and there was a different tingling at the back of his head.

/You are not going to die. Shut up and stop thrashing around, I cannot focus properly./

Bruce’s eyes snapped open, a little teary and wide as hell. WHAT was that…?

/Telepathy./

_GET OUT OF MY HEAD! NOW! NOWNOWNOWNOW!_

/Then STOP MOVING!/

The yell hurt inside Bruce’s head and he winced and forced his body to go limp. The buzzing feeling in his skin subsided, or more like penetrated deeper into his body, and it wasn’t really pleasant but it also did not really hurt. When he stopped struggling, he also realized that Loki wasn’t as much strangling him as holding him down, and the pressure on his windpipe also eased up once he calmed down.

“Please don’t kill him?” Dick piped up from behind Loki – the god just snorted, and continued to stare at Bruce intently. It felt… unnerving, to say the least.

“I’m not yet old enough to become Batman,” Dick finished and Loki snorted again, this time a little like laughter, and Bruce, if he wasn’t busy trying to not wince, would really GLARE at Dick. Which probably wouldn’t work since Dick was bigger than him now.

“I can rid you of this curse,” Loki said in the end and pulled his hand away. Bruce coughed and sat up, all his muscles sore and strained as if he had been in a particularly bad fight. He frowned at the god, rubbing his abused neck.

“I’m not asking for YOUR help.”

“Then you better start, because you have about three days to live,” Loki smiled nicely and Bruce grit his teeth.

One of his back molars fell out. Bruce spat it out into his hand and glared at the god.

“Please,” he hissed, thinking of the beautiful future when he would again be his normal size and thus capable of kicking Loki’s ass for being so SMUG about this.

………………………………

If Bruce had though that the worst part was over, he had been sorely mistaken. He scowled and pouted and glared, but it did not help him in the slightest. He had never truly appreciated the impact of his height and muscle mass on people’s willingness to listen to him…

…or maybe those factors wouldn’t matter here anyway. This was LOKI, after all. As far as Bruce knew, the god did not make it a habit to listen to anyone.

“I WANT to be just turned back into an adult immediately,” Bruce tried a growl again, but judging by Loki’s bored expression, it was obvious that he failed.

“I cannot do that. This kind of magic is extremely complex. Your body would not withstand it all at once.”

Bruce gritted his teeth and tightened his hands into fists, feeling VERY much like kicking Loki in the face. He visualized it for a few seconds, just to calm down (and because he knew Loki was rummaging in his head), then sighed.

“How long will it take?”

“A few weeks. Maybe a month,” Loki guessed and Bruce really felt like whining at that moment… but it was embarrassing enough that Dick was grinning at him, about two or three inches taller.

All he could really do was wait and hope that Loki knew what he was doing.

………………………

“I didn’t turn back,” Bruce snorted in the morning.

“Obviously,” Loki agreed with a sneer. “I TOLD you so yesterday. I cannot reverse the curse in one day.”

“Maybe you should try harder,” Bruce growled and studied his still too small hand. “I’m not even a day older than yesterday,” he huffed, disappointed, and glared at Loki… who just smirked irritably:

“But you are not younger either, yes?”

Bruce frowned at the god suspiciously.

“You are not trying to keep me out of the way by making me stay ten forever, are you?!”

Loki snickered at that, shaking his head at Bruce and offering a very, very condescending smirk.

“Trust me, Wayne, you would not pose any danger for me even if you turned into a giant.”

Bruce was so offended by those words that his only reply was to stalk to the bathroom and slam the door REALLY hard after him. He HATED Loki.

………………..

“You can’t keep spelling me asleep!” Bruce hissed the next morning when he realized the last memory he had of the previous evening was that of him yelling at Loki that he didn’t need a calming spell before the healing began again… and Loki’s condescending smirk.

“As you wish,” Loki said, head buried in some science journal, which Bruce doubted he understood… but he was not going to ask.

The last thought of THAT particular evening was ‘fuck, I should have specified ‘no potions in my tea either.’

………………………….

The worst part, however, was the boredom. The Justice League had a new case, some mutant babies where they should have been born normal, and they suspected that Project Cadmus was behind it: however, Lucius flat-out refused to make a child-costume for Batman (and asking Dick for an old Robin costume was too humiliating), J’onn and Superman uneasily pointed out that in his current form, Batman would not really be much of an asset to the team, Wonder Woman looked as if she was restraining herself from hugging Bruce (which, even in his current form, she would REGRET, Bruce would make sure of that)… and Loki snorted, rolled his eyes, told them all that they were imbeciles (in much more poetic terms) and dragged Bruce away by his collar.

“Show some respect,” Bruce barked when he had been deposited on his own bed unceremoniously, and the god smirked ironically:

“Grow up.”

Bruce groaned in frustration and kicked in the general direction of Loki’s knee – the god simply stepped away with a raised eyebrow.

“You are not in any state to chase anything except a ball of yarn,” Loki continued and Bruce glared at him. He HATEDHATEDHATEDHATEDHATED Loki.

“That’s your fault. You could fix me,” he huffed and crossed his arms over his chest. It was disconcerting to feel just bones and ribs there instead of solid muscle.

“I said I could not,” Loki frowned. “If you think your company is such a great asset to my life that I would voluntarily prolong the misery, you are mistaken.”

“Then why help me at all?” Bruce stared at the god, who simply shrugged:

“Batman is order and chaos both,” he stated.

Bruce lifted an eyebrow at that cynically:

“How romantic.”

“And Stark hates you,” Loki added with a smirk, and stepped closer to bed for another round of magical treatment.

…….

To say that Loki’s healing magic was unpleasant would be the understatement of the century, maybe of a millennium. Bruce’s bones were constantly on fire, he could barely move without wincing (but he managed, he was BATMAN, dammit), and his muscles permanently felt like he had just been a part of a fight gone wrong involving a fifty-foot robot. His head, his eyes, his TEETH, everything HURT, and it did not help that Loki and Dick bonded over video games, since Dick seemed to find the whole situation largely amusing now that Bruce was out of mortal peril.

“It’s not FAIR if you put an illusion spell over my half of the screen!” Dick yelled and punched Loki’s shoulder – the god merely sniggered. Bruce watched them from the doorway, wondering what was weirder: to see a Norse deity with an Xbox controller in his hands, or to see Dick punching a supervillain who didn’t try to retaliate.

The game beeped to an end, Loki apparently winning (though unfairly), and Dick leaned back on the couch, staring at the ceiling.

“He’ll be okay, won’t he?”

Loki turned to him, and Bruce held his breath. Maybe he’d learn something Loki did not wish to tell him personally… but then again, that would presume some kind of a personal regard for Bruce’s feelings, which wasn’t exactly what he would expect from the god.

“Yes,” Loki agreed simply, then Dick huffed and punched the air:

“But he was SUCH a grumpy kid,” he grumbled, and Loki laughed (while Bruce tightened his fists, frowning in the shadows. He wasn’t GRUMPY.):

“Oh, he’s in agony,” Loki chirped, as if it actually pleased him, and Bruce almost snorted. The bastard was actually happy about all the pain. Figured.

Dick blinked at Loki suspiciously:

“Agony?”

“Well, maybe not so much agony as great ache. But I have to reverse the processes of his cells, and grow the ‘old’ ones through magic. That hurts a lot.”

Dick nodded at that… and chuckled at Loki:

“Can you make me older too?”

Bruce frowned, ready to step in, when he saw the god shake his head.

“No. Treasure the youth you have.”

Dick pouted, and Bruce almost felt a little less hatred towards Loki… until the god snickered and patted Dick’s head:

“You will have all the time to become a grumpy old ball of nerves like Batman.”

Dick giggled, and Bruce stalked off, deciding to REALLY aim properly the next time he attempted to kick the god.

……………………………….

Bruce gained an inch or two and about a year of age every morning, but it was still an excruciatingly slow process. Moreover, it turned out that Loki was right not to let him do any League business: Bruce’s muscles apparently suffered by the sudden loss of mass, and thus, after an hour-long work-out with a boxing bag that would hardly leave him breathless before and now left him nearly comatose, Bruce had to admit that he was NOT in the best shape.

He solved it as he usually did when the problem was HIM: when things could not be forced, apparently more force needed to be exerted.

The result was that his body ached a LOT more than before, but he always fell asleep even without magic now, which was good: he didn’t trust too much magic around himself, and considering the circumstances, the mistrust seemed to be rather well-placed.

He was at the stage of his life which he’d hated the most: while Bruce Wayne had never exactly been a scrawny, ugly kid, his hormones acted up just as well, and waking up with a hard-on wasn’t something he would enjoy – especially not if waking up (and all things connected to it) could not be done in private these days. Loki was always there, smirking, and Bruce had no way of hiding the state he was in.

To his displeasure, Loki took amusement in fucking with his mind. He spent all day of Bruce’s fifteen-years-of-age in a female form, one that meant large breasts overflowing from a tiny corset and shapely thighs packed into tight leather: Bruce hated him to the very core of his rotten, godly being, but unfortunately, his cock was beyond caring about personality of a nice pair of legs, so it jumped up and down in excitement whenever Loki sashayed by, and Bruce felt like castrating himself if the god did not stop.

The next morning, his bones ached a bit less, but a damp spot in his pyjamas reminded him of a dream he would’ve rather NOT had, and he had to glare at Loki and hope that it was just Loki’s way of getting into his head, NOT Bruce’s own subconscious turning rather weird.

Loki simply smirked from his chair and Bruce could feel the god’s eyes on his back as he rushed to the bathroom.

He spent the day lifting weights and imagining Loki’s head was the punching bag.

…..

“I am grown enough to handle this!” Bruce yelled when the Bat-signal appeared, and Loki spell-stuck him to a chair.

“No,” the god answered flatly and Bruce growled, trying to free himself – but unfortunately, magic had no mechanism he could figure out, so he was left thrashing on a chair like a fish out of water, glaring at the god.

“You handle it then!” he yelled among the insults, hating his hormonal teenage self at least as much as Loki at the moment. “Gotham is apparently in danger and you want me to just SIT here?! I told you SO many times to let me grow FASTER, that I can HANDLE it, but NO! It’s YOUR fault!”

 To his surprise, the god did not sneer. He just looked at Bruce and then walked out, and Bruce really, REALLY hoped that nothing bad would happen.

……….

“WHAT is this?!” the seventeen-something Bruce slammed the morning newspaper on the table in front of Loki, who had the audacity to look at him like an 18th century English nobleman disturbed out of his morning tea routine by an unexpected outburst of someone’s emotions.

The title page read _Mysterious Death of Runner-Up Congressman: Another Harvey Dent?_

Loki merely cocked an unimpressed eyebrow at the photo of the crime scene and shrugged.

“He was stealing money.”

“SO YOU KILLED HIM!?”

“Yes.”

“YOU’RE ADMITTING IT JUST LIKE THAT?!”

“Would you rather I lied?”

Bruce threw up his hands in the air, then scowled back at the god.

“We don’t just KILL people because they’re stealing around here!”

“ _You_ do not,” Loki corrected him and Bruce huffed.

“Exactly. Don’t ever do something like that again. Just finish your job and _go._ Understood?!” he growled, his voice finally getting closer to the Batman standard, and stalked off.

That night, he understood what true agony meant – his whole body was on fire, his brain felt like it was frying in his skull and he couldn’t even as much as shift in the bed without it HURTING as fuck, searing streaks of white-hot pain coursing through every inch of his body.

He figured it was Loki’s way of saying ‘you ungrateful little prick.’

Next morning, he woke up slightly over nineteen or thereabouts, sore and unable to move a finger, head thudding and eyes stinging, lips dry and cracked and bitten-through.

Loki brought him tea without a word. Bruce did not ask to be aged faster again.

…………………..

It was two days before he could really move. Loki did not come into his room or attempt any more aging magic. Bruce slept a lot: whenever he woke up, there was more fresh tea on his bedside table, but no one in the room. He was thankful for the gesture and decided to not overthink whom to be thankful to.

One good thing about being BEAT was that he sported no erection in those two days, even if his dreams were chaotic and filled with more naked flesh than Bruce would have liked to.

When he finally shuffled to the bathroom, a little sore but otherwise fine, he definitely did not expect Loki to appear, his presence tingling over Bruce’s bare back as the god stood a mere inch behind him.

“You want me,” the god whispered right into Bruce’s ear and made him shiver. He scowled at Loki, who was still (dammit) taller than Bruce, in the reflection of the mirror, but the god simply smirked back, his green eyes an intense, piercing green in the neon-sharp light of the bathroom.

“Go away,” Bruce said, and instantly hated his throat for once again raising his voice an octave where he wanted it low and dangerous. Loki raised his arm slowly, his fingers not-quite-touching Bruce’s skin, but he found himself shivering as he watched Loki’s reflection in the mirror half-close his eyes and lean in, nearly brushing the tip of his nose against Bruce’s ear.

“We can do something about that…”

Bruce’s breath hitched in his throat and he elbowed Loki-

-at least he tried to. His arm went through thin air and Loki’s magical clone shimmered out of existence. Bruce could almost hear chuckling in the air and turned back with a growl, punching the mirror instead out of sheer frustration, half-hard and ashamed of himself.

He did not lust after gods- no, MEN. EVER. He’d spent a CONSIDERABLE part of his life among men in TIGHTS and he never, not even once, stopped to admire a colleague’s (or an enemy’s) buttocks or legs or arms.

Damn the stupid god of lies. Now, Bruce’s own BODY was a lie, because he was NOT lusting after Loki. NO way.

…………………

Loki made it a point to breach Bruce’s personal space on every occasion. He always made it look like an accident, and Bruce was doing his best to regain the perfect control of his reactions, so no confrontation was in store for the two of them: but the truth was that Bruce’s dreams were more often than not filled with green eyes half-lidded in the throes of passion and it was unnerving as fuck, especially when he asked J’onn to bring around some of those anti-mind-control and anti-telepathy headbands… and the only result was that he had a headache from the discomfort the next day, along with the typical morning wood.

Bruce counted days until he was his normal self: he spent his time training, mostly, and he was slowly getting back into shape. He anxiously awaited the moment when Loki would say that he was alright… but the moment seemed to take forever. Loki offered some vague explanation about how he had to tread carefully to not damage his body, but it sounded like a load of bull to Bruce the more he listened to it.

Then, a morning came (Bruce did too, in his sleep, dammit) when he realized that he had not been as sore as he had been during the teenage years for quite a few days… and he glared into the mirror.

It was Batman’s glare.

And Batman was NOT happy.

Bruce – Batman – searched his house, trying to catch a glimpse of the villainous god, but he was nowhere to be seen. Finally, Bruce found him in the Bat-cave, rummaging through Batman’s weapons, and that was too much. He stalked to the god and grabbed his shoulders, spinning him around.

“You conniving little bastard,” he hissed, and Loki’s unimpressed eyebrow-cocking did not do much to assuage his anger.

“What can I do for you?”

“Why did you lie about me not being healed properly?! And if you as much as attempt to lie again, I swear I’ll…”

“What?” Loki smirked and slithered out of Batman’s grip. To his surprise, Loki didn’t run away or teleport elsewhere, instead, his arms snaked around Batman’s neck. Damn the bastard god for still being an inch taller.

“You’ve had your fun, trickster,” Batman growled, catching Loki’s wrists roughly. Loki’s eyes sparkled at that, and Bruce, underneath his Batman being, realized with horror that that was EXACTLY the look he’d seen in his dreams.

And that Batman did not mind at all.

“Now it’s my turn,” Batman growled before he pushed Loki into the rocky wall of the cave and pressed them together to get what he’d wanted for quite some time.


End file.
